The present invention relates to a compact video camera recording and play-back device and, more particularly, it relates to a video camera recording and play-back device to which a camera is incorporated in one body (hereafter called a video camera recorder). Heretofore, the chassis of a conventional video camera recorder is made of metallic plates, in order to install printed circuit boards such as a main printed circuit board, a head amplifier printed circuit board and a camera printed circuit board onto the chassis, and an insulating member had to be placed between the chassis and the boards, and each board had to be electrically connected with flexible circuit boards. Printed circuit boards are hereafter referred to as "PCB".
The metallic chassis for the video camera recorder has brought many disadvantages to the camera recorder, requiring, for example considerable assembly time and production costs for extra parts. Furthermore, the extra parts make the video camera recorder heavier.
Another problem in the metallic chassis is that a rotary head cylinder is fixed to the chassis with screws through a cylinder installing base, and catchers which are positioning members of guide rollers at the bottom are also fixed to the chassis with screws, and the cylinder installing base and the catchers are independently fixed onto the chassis. The assembly work of the cylinder and guide rollers is troublesome, and often lacks accuracy.
Further, as is shown in FIG. 19, a ring gear 51 provided in this kind of a tape guide assembly was rotatably installed on the (not shown) chassis by applying three flanged guide rollers 52, for positioning against the engaging pinion 50 as to be parallel to the chassis (see the publication of examined patent application Showa 63-318672).
Further, as is shown in FIG. 20, the tape guide assembly 56 was connected to the horizontal ring gear 51 through a connecting member 89, and travelled along guide groove 46 on a sloped guide plate 47 while moving up and down along a circular arc, in accordance with the rotation of the ring gear 51. But in this construction, a plurality of flanged guide rollers 52 was required, and there was a further drawback in that connection of the tape guide assembly 56 to the ring gear 51 is very complicated.
Furthermore a mode changing switch of this kind of magnetic recording and play-back device was fixed on the chassis with small set screws and connected to the PCB with lead wires. Therefore, in this construction, as there are connecting parts between the mode changing switch and the PCB, there was a long-felt desire to decrease the number of parts, and to make the device smaller.
In the conventional device, for grounding the upper cylinder of the rotary head cylinder, the lower cylinder was fixed on the metallic chassis with several screws and the grounding between the upper cylinder and the static lower cylinder was provided together with grounding the upper cylinder by installing an earth-brush assembly. Therefore, when using a plastic chassis, as it becomes impossible to ground the rotary head cylinder, and too many extra parts were necessary for assembly.
In addition, the ring gear 51 which rotates the tape guide assembly along the tape guide rail for winding the tape around the periphery of the rotary head cylinder with a certain rounding angle was rotatably supported by three flanged guide rollers 52 as shown in FIG. 20. Therefore, in this construction, it was necessary to drill holes for installing the flanged guide rollers installation took a considerable time.
In this conventional magnetic recording and play-back device, in order to wind the tape around the rotary head cylinder with a certain angle, it was necessary to revolve a pair of tape guides while sliding along the rail guides, and to make the tape guides contact the catchers placed at the terminal points so that the tape guides are elastically pushed against the catchers. It also was required to bridge each spring against each upper ring gear and the lower ring gear, and to obtain the required contacting force by applying these the application of such springs. Accordingly, this construction not only forced a tape loading motor to bear excess loads for elastically pushing the guide rollers to the catchers, but required a considerable number of parts owing to the complex construction.
Furthermore, in the construction which elastically pushes the conventional pinch roller to a capstan roller, it was necessary to caulk bosses into the ring gears and to obtain the pushing forces of the pinch rollers against the capstan roller by revolving the lever with these bosses. By applying this construction, ring gears were forced to be loaded with considerable force towards rotational directions, even if ring gears were stopped while the video camera was used. Therefore, as the strength of ring gears was required to be large enough to bear the added forces, up to the present, ring gears made of metal were used.
Furthermore, in the compact video camera recording and play-back device which uses the conventional rotary head cylinder, the arm having an inclined post for guiding the tape was swung by a cam mechanism. Accordingly, it required considerable assembly time due to the complex construction for revolving the cam mechanism.
Furthermore, as the cassette holder of the conventional video camera had structural weak points corresponding to the gripping position in opening the holder, and opening and closing could not be performed smoothly, due to distortion or bending of the cassette holder itself. Especially in pushing only one side of the cassette holder, and there occurred the problem of not closing, due to the distortion of the cassette holder.
This invention was developed in consideration of the above-mentioned drawbacks, and the object thereof is to provide a compact video camera recording and play-back device which can be easily handled, has less parts, decreased weight, simplified assembly, and reduced manufacturing costs.
Further, the other object of this invention is to provide a video camera recording and play-back device which has high accuracy and high grade image quality, by integrating a revolving head installation base and lower positioning portions of the guide rollers into one piece.
Another object of this invention is to provide a video camera recording and play-back device having a simple construction, easy assembly and higher reliability, and also a long life.
Yet another object of this invention is to provide a new construction of the plastic cassette holder, provided with a synchronized shaft shaped in one piece with the cassette holder, and free of the above-mentioned drawbacks.
In order to attain the above objects, the video camera recording and play-back device according to this invention is characterized in that the chassis is made of plastic and the first PCB is assembled through the connecting members with the chassis.
Also, the device is characterized in that the second PCB is supported by the supporting members installed in one piece with a plastic chassis, together with the second PCB assembled on the aforementioned first PCB.
Furthermore, the device is characterized in that the first PCB and the second PCB are electrically connected with a connecting member.
The device is further characterized in that the plastic frame is molded in one piece with a plastic chassis, on which the rotary head cylinder with magnetic heads is installed.
The above-mentioned rotary head cylinder is constructed so as to be suited to the rotary head cylinder for the portable video camera. Accordingly, by providing this construction, it becomes possible for the device to be easily assembled in comparison to the conventional device, and possible to reduce the assembly work, further reducing the cost of parts due to the reduction in the numbers of parts, and finally to obtain a light-weight device.
Further, in the video camera recording and play-back device of the present invention the lower part of the guide rollers on the moving guide are supported by the supporting member installed on the chassis, the top head portion of the guide rollers is supported by upper guides, and the upper guide is provided with U-shaped notches for supporting the head portions of the guide rollers. Further, the chassis and the upper guides are separately molded, and each of them is made of plastic. By applying these constructions, the device has the following advantages. Namely,
(1) it is possible to assemble the device with high accuracy and to obtain high grade vision, as the rotary head cylinder installing portion and the V-shaped portions for positioning the lower portion of the guide rollers are shaped in one piece with the chassis, PA1 (2) it is possible to reduce the number of parts, and to reduce assembly work, as the rotary head installation portion is shaped in one piece with the chassis. PA1 (1) as there is no need to provide a plurality of flanged guide rollers around the internal periphery of the ring gear as provided in the conventional device, it becomes possible to reduce the number of parts; and PA1 (2) as two ring gears are installed so as to incline in the same direction as the running direction of the tape guide assembly and with the inclination of the assembly in set-up condition, then the tape guide assembly is able to follow the revolution of the ring gear within the play range of the engaging portion, therefore making it possible to reduce the number of parts and assembly work owing to a more simple construction than that of the conventional device. PA1 (1) it is possible to securely ground the revolving head cylinder by using simple construction, and PA1 (2) as the earth brush assembly is fixed together with the lower cylinder, it reduces the fastening steps. PA1 (1) As it is possible to elastically push the guide roller of the lower tape guide assembly and the guide roller of the upper tape guide assembly against the catcher by applying only one tension spring, the load required for the tape loading motor is reduced. Especially in case of application of this construction to video cameras, it becomes possible to extend the life of batteries. PA1 (2) As it is possible to bias both the upper ring gear and the lower ring gear by applying only one tension spring, it becomes possible to simplify construction, and to decrease the number of parts. PA1 ring gears driving tape guide assemblies, PA1 a worm gear engaged with one of the ring gears, and driven by a motor, PA1 a slide plate supporting the worm gear, and having an inclined portion, PA1 the first revolving plate having a stopper, PA1 a roller installed on the first revolving plate, and contacting to the inclined portion of the slide plate, PA1 the second revolving plate revolving around the axis of the first revolving plate, and contacting to the stopper at the one end of the plate, PA1 a pinch roller rotatably installed on the second revolving plate, PA1 an elastic member bridged between the first revolving plate and the second revolving plate, PA1 (1) In this construction, as the pinch roller is pushed against the capstan through the transferring roller while being pressed by the inclined portion of the sliding plate, the reaction force of the pinch roller directly is not added to the worm gear. As the direct reaction force does not effect the lower ring gear, it becomes possible to prevent deformation of the ring gear. PA1 (2) Because of the reason described in (1), as the strength of the ring gear is perhaps not strong, it becomes possible to make the ring gear from resin such as plastic, to economize expenses. By employing a plastic ring gear, it is also possible to decrease the weight. PA1 a rib shaped on the upper ring gear; PA1 the first arm member revolving while being engaged with each end of the rib of the upper ring gear when loading and unloading the tape, PA1 a revolving plate co-revolving with the first arm member in one piece, and having a gear integrated in one piece, PA1 the second arm member having an inclined post and one gear engaged with the aforementioned gear of the revolving plate,
Furthermore in the video camera recording and play-back device of this invention, tape gear assemblies which are connected with an upper ring gear and a lower ring gear, are driven by the rotation of said upper and lower ring gears, a rib along the internal periphery of the lower ring gear being built on the chassis in one piece with the chassis, and another rib along the internal periphery of the upper ring gear being built on the lower ring gear in one piece with the lower ring gear. This device has the lower ring gear slantingly installed on the flat surface of the chassis, a link mounted on the lower ring gear, and a tape guide assembly pivotably installed on the tip portion of the link. The pin hole of the link mounted on the lower ring gear is the shape of a long hole. Further, it is preferable that one of the upper ring gears or the lower gear be made of plastic, as well as the plastic chassis. The ribs are formed in circular arcs. By applying these constructions, the device has the following advantages. Namely,
Furthermore, in the video camera recording and play-back device of the present invention, the mode changing switch for changing the working mode of the device is directly installed on the PCB, and the switch is driven by the motor through a gear mechanism. By applying these constructions, as the connecting parts installed between the mode changing switch and the PCB are able to be eliminated, it becomes possible to reduce the cost of parts and assembly time for assembling the connecting parts, and consequently, this device has the advantage of increasing productivity.
Furthermore, in a video camera recording and play-back device according to the present invention, an elastic metal chip contacted to the axis of the rotary head cylinder is connected to the grounding circuit installed on the PCB through connecting members. Also, the metal chip and the connecting members are built in one piece, and the connecting members are made of aluminum. Further, the rotary upper cylinder and the fixed lower cylinder are electrically conducted through the metal chip and the connecting members, and the connecting members are fixed on the chassis which is made of plastic. By applying these constructions, the device has the following advantages:
Furthermore, the video camera recording and play-back device of the present invention is provided with a pair of ring gears for driving the tape guide assemblies which guide a tape on to the rotary head cylinder, and at the vicinity of the specified portion where the rotary head cylinder is installed, a hollow space penetrating through the chassis is provided, and the hollow space is located in between the positioning place of the tape guide and the ribbed portions supporting the base portions of the tape guide assemblies. Also, one of the two ring gears is partly mounted under the ribbed portion behind said hollow space and another ring gear is mounted on the ribbed portion above the hollow space. By applying these constructions, it becomes possible to install the lower ring gear, by inserting one portion of the gear into the space, and then throwing down toward the opposite direction, therefore becoming possible to eliminate the flanged guide rollers used in that conventional device, and to further realize a reduction in the number of parts and assembly work.
Furthermore, in a video camera recording and play-back device which revolves an upper ring gear and a lower ring gear, and drives each of the tape guide assemblies incorporated in ring gears, the video camera recorder and play-back device of this invention is provided with an elastic member which energizes the upper ring gear and the lower ring gear in opposite directions from each other, a worm gear engaged to the lower ring gear is supported by a first sliding plate, a gear engaged to the upper ring gear is installed on a second sliding plate, and the first and second sliding plates are bridged by the biasing elastic member.
On the second sliding plate, the first gear engaged to the lower ring gear, the second gear engaged to the first gear and the third gear assembled coaxially and in one piece with the second gear are installed, and the second gear revolves more slowly than the first gear. Also, on another end of the second sliding plate, the elastic member composed with a tension spring is bridged. Then, when the worm gear moves forward, as the tension spring bridged between the first sliding plate and the second sliding plate is extended, there is generated the rotating force acting towards the opposite direction between the lower ring gear engaged with the worm gear and the upper ring gear engaged with the gear installed on the second sliding plate. Accordingly, the guide rollers on the upper and lower tape guides fixed to each of the upper and lower ring gears are pressed to the catcher under the energized state. Therefore, the tape is wound around the revolving head cylinder with specified contact angle.
By application of the above construction, the following advantages are obtainable:
Further, the video camera recorder and play-back device according to this invention comprises with:
and furthermore, the sliding plate lets the first revolving plate revolve by moving itself and a straight line, and one of the ring gears is made of plastic.
Accordingly, the roller installed on the first revolving plate elastically pushes the pinch roller against the capstan, pushes the pinch roller against the capstan, by applying the inclined portion of the slide plate, but in this case, the reaction force of the pinch roller is not transferred to the worm.
Accordingly, as the ring gear does not receive an excessive load, it maintains high reliability and a long life.
According to this invention, it is clear that this device has the following advantages:
Further, in a video camera recorder and play-back device which revolves an upper ring gear and a lower ring gear and drives each of the tape guide assemblies incorporated in the ring gears, the video camera recorder and play back device according to this invention is provided with:
and further on the first arm member two engaging portions engaged to the rib, and the rib shaped as a concentric circular arc-shape to the upper ring gear.
Accordingly, when the upper ring gear rotates loading direction or unloading directions, the first arm member engaging to the rib revolves, then the revolving plate fixed to the axis of the arm member also revolves, then the gear fixed to the revolving plate also revolves, successively the second arm member having an indicated post and engaging to the gear also revolves, and accordingly the inclined post swings to the specified position, then the tape is guided as specified.
Furthermore, the cassette holder according to this invention is constructed to form a pair of door hinge portions by elongating both side walls of the holder, and a synchronous shaft is mounted between both door hinge portions, and is constricted so as to be rotatable around the synchronous shaft.
Also, at another end of the cassette holder, a cassette housing room is formed, and a pair of elastic members are installed in the synchronous shaft for biasing the cassette holder to open, and the cassette holder is made of resin such as plastic.
Accordingly, the cassette holder according to this invention is constructed so as not to produce strains, and is provided with the advantage of preventing malfunctions, for example, it readily works even when one side of the holder is pushed and strained.